1. Field of the Invention
The present invention relates generally to transmission and reception of signals in a multi-cellular network. More particularly, the present invention relates to a method and apparatus for allowing cells to simultaneously transmit and receive signals with minimized influence of interference signals in a network where a plurality of cells exist.
2. Description of the Related Art
In a multi-cellular network, in order to maximize the efficiency of wireless resources, Base Stations (BSs) simultaneously transmit signals to a plurality of users (i.e., user terminals) using the same wireless resources (time, frequency, or code), which may cause a reduction of the performance of the entire network due not only to Inter-User Interference (IUI) in a cell, but also to Inter-Cell Interference (ICI).
Various studies have been made to increase the throughput of the system in the multi-cellular network. Technology for improving the performance by sharing channel or data information between BSs is referred to as ‘BS cooperative communication’. However, this communication technology based on the cooperation between BSs has a shortcoming in that an excessive amount of backhaul infrastructure needs to be built.
Recently, an interference alignment technique has emerged, that secures subspaces which are not affected by interference signals, by aligning interference signals incoming from other cells to some subspaces (or in some directions) among attainable signal spaces. Signal spaces in the interference alignment technology may be secured by expanding the time, the frequency or the number of antennas. Technology for applying the interference alignment technique in the multi-cellular network by expanding the number of antennas has been studied.
However, the related-art technology merely limits the number of cells in the network to two, and the number of users in a cell to two, but has not presented a specific way for the interference alignment technique that can be applied to a situation where the number of cells and the number of users in a cell are not limited.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.